Install CMake modules local

The CMake modules should be installed local into ~/install/cmake/modules or similar.
When following the current instructions 6.1: Install additional CMake modules, it's impossible to do a non-root installation, because "kdelibs/cmake/modules/cmake_install.cmake" wants to install the modules to "/cmake/modules". (I didn't install CMake local, because my system already provided CMake > 2.4.3).

I've already tried to do this, fiddling around with CMAKE_MODULE_PATH and DATA_INSTALL_DIR but couldn't get it working.